1. Field of the Invention
The present invention relates to a video printer which performs thermal transfer type printing of color images and the like using photographic printing paper cut into sheets.
2. Description of the Related Art
There are conventional video printers having a configuration wherein a sheet of paper cut from photographic printing paper to a size such as A3 is fed from a paper feeding tray to a platen and is pressed onto and wound around the outer circumference of the platen by a plurality of pinch rollers; an ink ribbon stretched between a pair of reels is pressed against the sheet of paper on the outer circumference of the platen by a thermal head; the rotary drive of the platen transports the sheet of paper and the ink ribbon together with the sheet of paper simultaneously; and the transportation of the sheet of paper and the ink ribbon is repeated several times to sequentially overprint yellow, cyan and magenta (three primary colors) sublimating color materials (dyes), with which the ink ribbon is coated, onto the sheet of paper by thermal transfer, thereby printing a color image on the sheet of paper.
This type of video printer is configured so that the sheet of paper which has been printed is pressed against a motor driven paper-ejecting roller by a pressing roller and then ejected onto an ejected paper table beside the platen.
In a conventional video printer, the pressing roller is always pressed against the paper-ejecting roller in all the modes thereof, i.e., the paper-feeding mode wherein the sheet of paper is fed from the paper-feeding tray to the platen, the printing mode wherein the operation of transporting the sheet of paper together with the ink ribbon by means of the rotation of the platen is repeated several times with the ink ribbon pressed against the sheet of paper on the outer circumference of the platen by the thermal head, and the paper-ejecting mode wherein the sheet of paper which has been printed is ejected from the outer circumference of the platen onto the ejected paper table beside the platen.
Therefore, in the conventional art, especially in the printing mode, the sheet of paper is pressed onto the outer circumference of the platen by the pinch rollers and is also pressed against the paper-ejecting roller by the pressing roller at the same time. As a result, both the platen and the paper-ejecting roller apply a driving force to the sheet of paper. Variations in the two driving forces can easily cause slippage and the like of the sheet of paper relative to the platen, resulting in damage to the printed surface immediately after printing, offset of the printed images, and the like.
In cases where the leading edge of the sheet of paper is brought between the paper-ejecting roller and the pressing roller immediately after printing, there is the problem that the impact causes unevenness in printing.
The present invention has been conceived to solve the above-described problem, and it is an object of the present invention to provide a video printer wherein two driving forces are not applied to the sheet of paper in the printing mode.